The goals of this project are to detect and accurately describe menstrual- ly-related mood disorders, explore their pathophysiology and response to pharmacological and environmental manipulation, and to document the relationship between reproductive endocrine change and disorders of mood as a way of further investigating the neurobiology of psychiatric illness. The longitudinal screening methods developed by this group are capable of distinguishing women with menstrually-related mood syndromes from those who only believe that they have such a syndrome. With these methods, we have identified the following: 1) the disocialbility of the premenstrual syndrome symptomatic state from the late luteal phase; 2) a significantly lower baseline cortisol and significantly increased CRH-stimulated cortisol in PMS patients compared with controls; 3) a therapeutic response in five of 22 patients treated with alprazolam and eight of 20 patients treated with thyroid hormone; 4) a 30% prevalence of abnormal response to TRH in PMS patients compared with controls; 5) an absence of differential neuroen- docrine response to clonidine infusion in PMS patients compared with controls; 6) a blunted LH response to GnRH in PMS patients compared with controls; 7) significant decreases premenstrually and increases post menstrually in libido in Pms patients compared with controls.